Protein turnover and energy\u00a0metabolism was simultaneously measured in sows on d 7 and 17 of lactation.\u00a0Sows were fed a lactation diet ad libitum (14 MJ DE\/kg, 20.7% crude protein,\u00a01.02 % total lysine). On days 7 and 17 of lactation, 24 h energy expenditure\u00a0was measured by indirect calorimetry while a primed-constant infusion of L-[1-13C]leucine (1.0 mg\/kg\/h) was delivered intravenously over 24 h to measure
\nrates of protein synthesis and breakdown. Milk yield and composition were\u00a0also measured. Leucine intake varied due to differences in feed intake, but\u00a0leucine flux was not significantly different between days of lactation. Protein\u00a0synthesis and leucine appearance from body protein breakdown, as % of flux,\u00a0were higher (P<.001) on d 7 than d 17 (81.1 vs. 76.9 % and 25 vs. -10 %),\u00a0respectively. The protein and leucine content of milk were also higher on d 7\u00a0than d 17 (5.3% vs. 5.1% CP and 3.0 vs. 2.0 g\/kg), respectively. Negative\u00a0protein breakdown on d 17 indicates utilization of leucine by the mammary\u00a0gland that was neither oxidation or protein synthesis. The higher dietary intake
\nof energy and protein on d 17 reduced both whole body protein breakdown\u00a0and protein synthesis. The higher dietary energy intake on d 17 (13.4 MJ\/d)\u00a0was entirely accounted for by milk energy output (13.8 MJ\/d).\u00a0These data indicate that sows were in greater protein deficit during early\u00a0lactation than late lactation; therefore diets higher protein, or with a better\u00a0balance of amino acids, are required in early lactation to reduce the loss of\u00a0body protein.<\/p>\n","protected":false},"excerpt":{"rendered":"
Protein turnover and energy\u00a0metabolism was simultaneously measured in sows on d 7 and 17 of lactation.\u00a0Sows were fed a lactation diet ad libitum (14 MJ DE\/kg, 20.7% crude protein,\u00a01.02 % total lysine). On days 7 and 17 of lactation, 24 h energy expenditure\u00a0was measured by indirect calorimetry while a primed-constant infusion of L-[1-13C]leucine (1.0 mg\/kg\/h) […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[18120,19],"tags":[1809,46,23138,7258,104,18011],"class_list":["post-14975","post","type-post","status-publish","format-standard","hentry","category-ontario-pork","category-pork-insight-articles","tag-acid","tag-feed","tag-lux","tag-milk","tag-sow","tag-tot"],"_links":{"self":[{"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/posts\/14975","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/comments?post=14975"}],"version-history":[{"count":2,"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/posts\/14975\/revisions"}],"predecessor-version":[{"id":14978,"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/posts\/14975\/revisions\/14978"}],"wp:attachment":[{"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/media?parent=14975"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/categories?post=14975"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prairieswine.com\/rsc\/wp-json\/wp\/v2\/tags?post=14975"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}